How SARS-CoV-2 binds to human cells

30 Mar 2020

Scientists are racing to learn the secrets of severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2), which is the cause of the pandemic disease COVID-19. On Friday, March 27 , 2020 Yuanyuan Zhan et al. from Westlake Institute of Advanced Study, Hangzhou, China, published in Science a study entitled Structural basis for the recognition of SARS-CoV-2 by full-length human ACE2. The first step in viral entry is the binding of the viral trimeric spike protein to the human receptor angiotensin-converting enzyme 2 (ACE2). Authors present the structure of human ACE2 in complex with a membrane protein that it chaperones, B0AT1. In the context of this complex, ACE2 is a dimer. A further structure shows how the receptor binding domain of SARS-CoV-2 interacts with ACE2 and suggests that it is possible that two trimeric spike proteins bind to an ACE2 dimer. The structures provide a basis for the development of therapeutics targeting this crucial interaction. Data were obtained using cryo-electron microscopy and details are presented with an overall resolution of 2.9 angstroms, with a local resolution of 3.5 angstroms at the ACE2-RBD interface.